Chlorophyll Degradation by Peroxidase in Parsley Leaves

Abstract

The mechanism of chlorophyll degradation by peroxidase in parsley leaves was studied. Chlorophylls present in the ethyl alcohol (EtOH) extract of parsley leaves were degraded by a peroxidase-hydrogen peroxide system. Purified chloro-phylls, however, were not affected by the system, suggesting the existence of a substance which acts together with peroxidase to degrade chlorophyll in parsley leaves. The substance was isolated from the EtOH extract by the methods of solvent fractionation and column chromatography. After hydrolysis, it was identified as an apigenin, which is a major flavonoid contained in parsley, by measuring Rf value on thin layer chromatogram and spectral characteristics. From the results obtained, it is concluded that in parsley leaves chlorophylls are not degraded by peroxidase directly, but that peroxidase oxidizes the apigenin and then the oxidized apigenin degrades chlorophylls.